1. Field of the Invention
The invention relates to a support unit for a cab in utilitarian vehicles.
2. Description of the Prior Art
A support unit of this type is known from DE-OS No. 15 55 946. In this known support unit, which is intended in particular for the driver's cab of a tractor, the valve body of the directional control valve is connected to an actuator which adjusts the directional control valve whenever the cab assumes a position deviating from the horizontal. As a result, the adjustment of the directional control valve is effected in a manner in which fluid is either drained from or fed into the support cylinder, in order to lengthen or shorten it, respectively, thereby compensating for a deviation of the cab from the horizontal position. The known support unit also includes a spring element which is intended to serve as an elastic attachment of the cab to the chassis of the vehicle, in order to protect the driver from the vibrations which are transmitted by the unsprung axles of the utilitarian vehicle. A spring connection of this type necessarily leads to vibratory and rocking motions of the cab relative to the chassis which may be absorbed to some extent but which, nevertheless, can be felt by the user of the cab and which may impair the safe operation of the vehicle in traffic.